EPA Removes Solvent from Toxic Chemical List

Published February 1, 2006

Manufacturers and users of the solvent methyl ethyl ketone (MEK) will no longer have to report to the federal government waste management information regarding the substance, the U.S. Environmental Protection Agency (EPA) announced on December 14.

The Clean Air Act (CAA) requires EPA to regulate toxic air pollutants. Currently, the agency regulates 188 compounds it considers to be toxic. EPA’s announcement came after extensive scientific research showed MEK poses no threat to human health or the environment.

Not Toxic or Harmful

MEK is a clear solvent used for lacquer, adhesives, cleaning fluids, and perfumes. Since 1996, the American Chemistry Council has been petitioning EPA to remove MEK from its list of toxic air pollutants. In response to the petitions, EPA began gathering scientific data on MEK in 1999.

In May 2003, EPA proposed to remove MEK from its list of regulated toxic air pollutants. “After carefully considering the 57 comments received on the proposal and reviewing scientific data demonstrating MEK’s low toxicity,” EPA explained, “EPA has taken final action to delist MEK as a hazardous air pollutant.”

According to an EPA fact sheet on MEK, “After extensive technical review and consideration of public comments, EPA has concluded that potential exposures to MEK that is emitted from certain industrial processes may not reasonably be anticipated to cause human health or environmental problems.”

Other Chemicals Also Delisted

EPA’s decision to cease regulating MEK under the Clean Air Act is not the first time the agency has delisted a chemical compound. EPA removed from its air toxics list caprolactam in 1996, long chain glycol ethers in 2000, and ethylene glycol monobutyl ether in 2004.

In addition, EPA’s decision to discontinue regulating MEK under the Clean Air Act is not the first time the agency has addressed a prior assertion of health hazards related to MEK. On June 30, 2005, EPA published a final rule allowing companies to stop reporting MEK emissions on EPA’s Toxics Release Inventory (TRI). EPA had favored keeping MEK on the TRI, but it removed MEK from the list following a federal appellate court’s determination that MEK was not toxic and posed no threat of harm to human health or the environment.

“At a minimum, the chemical must cause harm via human exposure” to be listed in the TRI, wrote Senior Judge Stephen Williams of the U.S. Court of Appeals for the District of Columbia Circuit in a May 2005 decision. “Because EPA’s own analysis demonstrates that MEK fails this test, EPA’s denial of the [American Chemistry Council’s] petition to delist was improper.”

Regulation Continues

Although MEK has been removed from the TRI and Clean Air Act regulation, EPA still will regulate MEK as a volatile organic compound because the agency asserts MEK, when mixed with other air particles, contributes to smog formation.

“The ongoing MEK saga illustrates how quick environmental activists–and often the federal government–are to errantly label a chemical as harmful to humans and the environment,” said Sterling Burnett, senior fellow at the National Center for Policy Analysis. “The MEK saga also illustrates how difficult and arduous it is to set the record straight. This should not have been an 11-year process, nor should it have required judicial intervention.

“Unfortunately, it is rare for science to prevail over alarmist propaganda,” Burnett noted. “Whether addressing mercury, arsenic, alar, or a myriad of other activist scares, usually the scientific truth gets swept under the rug. It is good to see that science triumphed over propaganda at least this once.”

James M. Taylor ([email protected]) is managing editor of Environment & Climate News.

For more information …

The EPA fact sheet on methyl ethyl ketone (MEK) is available online at http://epa.gov/ttn/oarpg/t3/fact_sheets/mek_fs.html.